Many structures, such as residential, commercial and industrial buildings, include gas and electric appliances, such as furnaces, hot water heaters, clothes dryers, stoves, and fireplaces that produce heated products when gas/air mixtures are combusted or heat is generated. The heated products of combustion or generated heat can contain waste products, such as carbon dioxide, carbon monoxide, excess heat, and/or particulates. For example, waste products are produced from heating water in a hot water heater such as carbon dioxide, carbon monoxide, and excess heat. An occupant could die if waste products, such as carbon monoxide, reach too high of levels within the structure. In another example, a gas or electric kitchen stove can generate unwanted heat and smoke to an uncomfortable level, making it desirable to remove the waste products from the structure. Therefore, these waste products have to be removed from the structure to provide a safe breathing environment and comfortable atmosphere for occupants, while allowing make-up air to be delivered back into the structure in proper proportion to meet air quality requirements.
Presently, exhaust systems do not make an efficient use of waste product heat before exhaustion from the structure. The waste products are exhausted with little or no heat exchange with the structural surroundings or cold make-up air that is being brought into the structure. Therefore, the overall efficiency of the appliances is reduced because the waste gases are exhausted from the structure at a temperature greater than the temperature within the structure. The result is a less efficient appliance and increased heating and energy costs.
The present invention addresses the increased costs and decreased efficiency associated with failing to effectively use the heat contained within waste gases generated from heated products sources, such as appliances. The present invention provides a novel heat exchange system that uses the heat of waste exhaust gases to increase the temperature of fresh air as well as increase the overall efficiency of a heated product source that is in use within a structure.